Defense Secretary Leon Panetta has given Israeli defense minister Ehud Barak a clear warning: don’t attack Iran. Panetta pointed to a U.S. analysis that a strike on Iran would set back its nuclear program, which Iran says is only for peaceful purposes, by one or two years at most. It would also have implications for U.S. forces in the region. He added that “thirdly, there are going to be economic consequences to that, that could impact not just on our economy but the world economy.” What to do, then, if a military strike would be both pointless and harmful? “The...